Go to the APT webpage. Follow the instructions there to download and install the latest version of APT onto your machine. You can also ask your system administrator to do an institution-wide installation.

Go to the Cycle 24 Announcement webpage. Download one of the templates to create your PDF attachment. There are separate template files for GO/SNAP and for AR/Theory Proposals. Template files are available in several popular word-processing applications, including LaTeX and Microsoft Word.